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REVIEW
GUIDE TO THE NATIONAL SCIENCE CONTENT STANDARDS FOR GRADES 9-12
+ THE ORIGIN AND EVOLUTION OF
THE EARTH SYSTEM | + THE ORIGIN AND EVOLUTION
OF THE UNIVERSE
The website links below provide a wealth of information
which reinforces the National Standards (Content Standard D) related
to the origins of the Earth and universe. These scientific concepts are
expected to be mastered after completion of a high school science program.
THE ORIGIN AND EVOLUTION OF THE
EARTH SYSTEM
The sun, the earth, and the rest of the solar system formed from a nebular
cloud of dust and gas 4.6 billion years ago. The early earth was very
different from the planet we live on today.
Geologic time can be estimated by observing rock sequences and using
fossils to correlate the sequences at various locations. Current methods
include using the known decay rates of radioactive isotopes present in
rocks to measure the time since the rock was formed.
Interactions among the solid earth, the oceans, the atmosphere, and
organisms have resulted in the ongoing evolution of the earth system.
We can observe some changes such as earthquakes and volcanic eruptions
on a human time scale, but many processes such as mountain building and
plate movements take place over hundreds of millions of years.
- How an earthquake occurs with animation and narration
- Earthquake damage at corresponding values on the
Richter
- Richter scale rating of recent quakes
- Earthquake explainer
- MichiganTechnological University—Everything
you ever wanted to know about volcanoes +
Link to Website
- Volcanic eruption-Hawaii
- Volcanic eruption of Mount Usu, Hokkaido, Japan +
Link to Website
Evidence for one-celled forms of life--the bacteria--extends back more
than 3.5 billion years. The evolution of life caused dramatic changes
in the composition of the earth's atmosphere, which did not originally
contain oxygen.
THE ORIGIN AND EVOLUTION OF THE UNIVERSE
The origin of the universe remains one of the greatest questions in
science. The "big bang" theory places the origin between 10
and 20 billion years ago, when the universe began in a hot dense state;
according to this theory, the universe has been expanding ever since.
Early in the history of the universe, matter, primarily the light atoms
hydrogen and helium, clumped together by gravitational attraction to
form countless trillions of stars. Billions of galaxies, each of which
is a gravitationally bound cluster of billions of stars, now form most
of the visible mass in the universe.
Stars produce energy from nuclear reactions, primarily the fusion of
hydrogen to form helium. These and other processes in stars have led
to the formation of all the other elements.
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